Atherosclerosis, a disease causing degeneration of the arteries, is characterized by the deposition of fatty substances in the inner coat of the arteries. Scientific research has shown that this fatty substance is cholesteryl ester, the storage form of cholesterol. In the normal artery the amount of this stored cholesterol is under stringent control and does not increase to the level where it damages the artery as in atherosclerosis. There is a protein in the inner coat of the artery that is responsible for the conversion of cholesterol to its storage form. This protein seems to be more actively converting cholesterol to its storage form in arteries that are affected by atherosclerosis. Part of this project is designed to determine if this increase is a cause or a result of the processes that cause atherosclerosis.